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									Search engine optimization                                                                                                      1

    Search engine optimization
    Search engine optimization (SEO) is
    the process of improving the visibility
    of a website or a web page in search
    engines via the "natural" or un-paid
    ("organic" or "algorithmic") search
    results. Other forms of search engine
    marketing (SEM) target paid listings.
    In general, the earlier (or higher on the
    page), and more frequently a site
    appears in the search results list, the
    more visitors it will receive from the
    search engine. SEO may target
    different kinds of search, including
    image search, local search, video
                                                                       A typical search engine results page
    search and industry-specific vertical
    search engines. This gives a website
    web presence.

    As an Internet marketing strategy, SEO considers how search engines work and what people search for. Optimizing a
    website may involve editing its content and HTML and associated coding to both increase its relevance to specific
    keywords and to remove barriers to the indexing activities of search engines. Promoting a site to increase the number
    of backlinks, or inbound links, is another SEO tactic.
    The acronym "SEO" can refer to "search engine optimizers," a term adopted by an industry of consultants who carry
    out optimization projects on behalf of clients, and by employees who perform SEO services in-house. Search engine
    optimizers may offer SEO as a stand-alone service or as a part of a broader marketing campaign. Because effective
    SEO may require changes to the HTML source code of a site and site content, SEO tactics may be incorporated into
    website development and design. The term "search engine friendly" may be used to describe website designs, menus,
    content management systems, images, videos, shopping carts, and other elements that have been optimized for the
    purpose of search engine exposure.
    Another class of techniques, known as black hat SEO or spamdexing, uses methods such as link farms, keyword
    stuffing and article spinning that degrade both the relevance of search results and the user-experience of search
    engines. Search engines look for sites that employ these techniques in order to remove them from their indices.

    Webmasters and content providers began optimizing sites for search engines in the mid-1990s, as the first search
    engines were cataloging the early Web. Initially, all webmasters needed to do was submit the address of a page, or
    URL, to the various engines which would send a "spider" to "crawl" that page, extract links to other pages from it,
    and return information found on the page to be indexed.[1] The process involves a search engine spider downloading
    a page and storing it on the search engine's own server, where a second program, known as an indexer, extracts
    various information about the page, such as the words it contains and where these are located, as well as any weight
    for specific words, and all links the page contains, which are then placed into a scheduler for crawling at a later date.
    Site owners started to recognize the value of having their sites highly ranked and visible in search engine results,
    creating an opportunity for both white hat and black hat SEO practitioners. According to industry analyst Danny
    Sullivan, the phrase "search engine optimization" probably came into use in 1997.[2] The first documented use of the
Search engine optimization                                                                                                    2

    term Search Engine Optimization was John Audette [3] and his company Multimedia Marketing Group as
    documented by a web page from the MMG site from February, 1997 on the Internet Way Back machine.[4]
    Early versions of search algorithms relied on webmaster-provided information such as the keyword meta tag, or
    index files in engines like ALIWEB. Meta tags provide a guide to each page's content. Using meta data to index
    pages was found to be less than reliable, however, because the webmaster's choice of keywords in the meta tag could
    potentially be an inaccurate representation of the site's actual content. Inaccurate, incomplete, and inconsistent data
    in meta tags could and did cause pages to rank for irrelevant searches.[5] Web content providers also manipulated a
    number of attributes within the HTML source of a page in an attempt to rank well in search engines.[6]
    By relying so much on factors such as keyword density which were exclusively within a webmaster's control, early
    search engines suffered from abuse and ranking manipulation. To provide better results to their users, search engines
    had to adapt to ensure their results pages showed the most relevant search results, rather than unrelated pages stuffed
    with numerous keywords by unscrupulous webmasters. Since the success and popularity of a search engine is
    determined by its ability to produce the most relevant results to any given search, allowing those results to be false
    would turn users to find other search sources. Search engines responded by developing more complex ranking
    algorithms, taking into account additional factors that were more difficult for webmasters to manipulate.
    Graduate students at Stanford University, Larry Page and Sergey Brin, developed "backrub," a search engine that
    relied on a mathematical algorithm to rate the prominence of web pages. The number calculated by the algorithm,
    PageRank, is a function of the quantity and strength of inbound links.[7] PageRank estimates the likelihood that a
    given page will be reached by a web user who randomly surfs the web, and follows links from one page to another.
    In effect, this means that some links are stronger than others, as a higher PageRank page is more likely to be reached
    by the random surfer.
    Page and Brin founded Google in 1998. Google attracted a loyal following among the growing number of Internet
    users, who liked its simple design.[8] Off-page factors (such as PageRank and hyperlink analysis) were considered as
    well as on-page factors (such as keyword frequency, meta tags, headings, links and site structure) to enable Google
    to avoid the kind of manipulation seen in search engines that only considered on-page factors for their rankings.
    Although PageRank was more difficult to game, webmasters had already developed link building tools and schemes
    to influence the Inktomi search engine, and these methods proved similarly applicable to gaming PageRank. Many
    sites focused on exchanging, buying, and selling links, often on a massive scale. Some of these schemes, or link
    farms, involved the creation of thousands of sites for the sole purpose of link spamming.[9]
    By 2004, search engines had incorporated a wide range of undisclosed factors in their ranking algorithms to reduce
    the impact of link manipulation. Google says it ranks sites using more than 200 different signals.[10] The leading
    search engines, Google and Yahoo, do not disclose the algorithms they use to rank pages. Notable SEO service
    providers, such as Rand Fishkin, Barry Schwartz, Aaron Wall and Jill Whalen, have studied different approaches to
    search engine optimization, and have published their opinions in online forums and blogs.[11] [12] SEO practitioners
    may also study patents held by various search engines to gain insight into the algorithms.[13]
    In 2005 Google began personalizing search results for each user. Depending on their history of previous searches,
    Google crafted results for logged in users.[14] In 2008, Bruce Clay said that "ranking is dead" because of
    personalized search. It would become meaningless to discuss how a website ranked, because its rank would
    potentially be different for each user and each search.[15]
    In 2007 Google announced a campaign against paid links that transfer PageRank.[16] On June 15, 2009, Google
    disclosed that they had taken measures to mitigate the effects of PageRank sculpting by use of the nofollow attribute
    on links. Matt Cutts, a well-known software engineer at Google, announced that Google Bot would no longer treat
    nofollowed links in the same way, in order to prevent SEO service providers from using nofollow for PageRank
    sculpting.[17] As a result of this change the usage of nofollow leads to evaporation of pagerank. In order to avoid the
    above, SEO engineers developed alternative techniques that replace nofollowed tags with obfuscated Javascript and
    thus permit PageRank sculpting. Additionally several solutions have been suggested that include the usage of
Search engine optimization                                                                                                   3

    iframes, Flash and Javascript. [18]
    In December 2009 Google announced it would be using the web search history of all its users in order to populate
    search results.[19]
    Real-time-search was introduced in late 2009 in an attempt to make search results more timely and relevant.
    Historically site administrators have spent months or even years optimizing a website to increase search rankings.
    With the growth in popularity of social media sites and blogs the leading engines made changes to their algorithms to
    allow fresh content to rank quickly within the search results.[20] This new approach to search places importance on
    current, fresh and unique content.

    Relationship with search engines
    By 1997 search engines recognized that webmasters were making efforts to rank well in their search engines, and
    that some webmasters were even manipulating their rankings in search results by stuffing pages with excessive or
    irrelevant keywords. Early search engines, such as Infoseek, adjusted their algorithms in an effort to prevent
    webmasters from manipulating rankings.[21]
    Due to the high marketing value of targeted search results, there is potential for an adversarial relationship between
    search engines and SEO service providers. In 2005, an annual conference, AIRWeb, Adversarial Information
    Retrieval on the Web,[22] was created to discuss and minimize the damaging effects of aggressive web content
    Companies that employ overly aggressive techniques can get their client websites banned from the search results. In
    2005, the Wall Street Journal reported on a company, Traffic Power, which allegedly used high-risk techniques and
    failed to disclose those risks to its clients.[23] Wired magazine reported that the same company sued blogger and SEO
    Aaron Wall for writing about the ban.[24] Google's Matt Cutts later confirmed that Google did in fact ban Traffic
    Power and some of its clients.[25]
    Some search engines have also reached out to the SEO industry, and are frequent sponsors and guests at SEO
    conferences, chats, and seminars. In fact, with the advent of paid inclusion, some search engines now have a vested
    interest in the health of the optimization community. Major search engines provide information and guidelines to
    help with site optimization.[26] [27] [28] Google has a Sitemaps program[29] to help webmasters learn if Google is
    having any problems indexing their website and also provides data on Google traffic to the website. Google
    guidelines are a list of suggested practices Google has provided as guidance to webmasters. Yahoo! Site Explorer
    provides a way for webmasters to submit URLs, determine how many pages are in the Yahoo! index and view link
    information.[30] Bing Toolbox provides a way from webmasters to submit a sitemap and web feeds, allowing users to
    determine the crawl rate, and how many pages have been indexed by their search engine.


    Getting indexed
    The leading search engines, such as Google and Yahoo!, use crawlers to find pages for their algorithmic search
    results. Pages that are linked from other search engine indexed pages do not need to be submitted because they are
    found automatically. Some search engines, notably Yahoo!, operate a paid submission service that guarantee
    crawling for either a set fee or cost per click.[31] Such programs usually guarantee inclusion in the database, but do
    not guarantee specific ranking within the search results.[32] Two major directories, the Yahoo Directory and the
    Open Directory Project both require manual submission and human editorial review.[33] Google offers Google
    Webmaster Tools, for which an XML Sitemap feed can be created and submitted for free to ensure that all pages are
    found, especially pages that aren't discoverable by automatically following links.[34]
Search engine optimization                                                                                                           4

    Search engine crawlers may look at a number of different factors when crawling a site. Not every page is indexed by
    the search engines. Distance of pages from the root directory of a site may also be a factor in whether or not pages
    get crawled.[35]

    Preventing crawling
    To avoid undesirable content in the search indexes, webmasters can instruct spiders not to crawl certain files or
    directories through the standard robots.txt file in the root directory of the domain. Additionally, a page can be
    explicitly excluded from a search engine's database by using a meta tag specific to robots. When a search engine
    visits a site, the robots.txt located in the root directory is the first file crawled. The robots.txt file is then parsed, and
    will instruct the robot as to which pages are not to be crawled. As a search engine crawler may keep a cached copy of
    this file, it may on occasion crawl pages a webmaster does not wish crawled. Pages typically prevented from being
    crawled include login specific pages such as shopping carts and user-specific content such as search results from
    internal searches. In March 2007, Google warned webmasters that they should prevent indexing of internal search
    results because those pages are considered search spam.[36]

    Increasing prominence
    A variety of methods can increase the prominence of a webpage within the search results. Cross linking between
    pages of the same website to provide more links to most important pages may improve its visibility.[37] Writing
    content that includes frequently searched keyword phrase, so as to be relevant to a wide variety of search queries will
    tend to increase traffic.[37] Updating content so as to keep search engines crawling back frequently and give
    additional weight to your site. Adding relevant keywords to a web page's meta data, including the title tag and meta
    description, will tend to improve the relevancy of a site's search listings, thus increasing traffic. URL normalization
    of web pages accessible via multiple urls, using the "canonical" meta tag[38] or via 301 redirects can help make sure
    links to different versions of the url all count towards the page's link popularity score.

    File Names
    Search Engines algorithms prefer that web pages files are really descriptive and relevant to the information displayed
    on the page. For SE to interpret a page properly its best that keywords are used instead of random characters and
    numbers. Each page should be optimized for a certain keyword or keyword phrases which should also appear in H1
    tag but also in the page file name. Since no spaces are accepted in the file name, hyphens and underscores are

    Google SEO
    Google holds over 60% of the total search market.[39] Its algorithm is naturally also unique, so ranking on Google
    carries its own unique considerations. Although there are over 200 criteria Google uses to rank sites, they can be
    categorized into two main sections: on-site and off-site factors:
    Google values sites that deliver quality content, relevance, easy navigation and load and an overal user-friendliness
    to the site’s visitors (on-site). However, a site’s popularity is heavily weighted when Google ranks sites (off-site).[40]
    Thus Google was originally designed to rank sites mostly based on the number of inbound links they were receiving
    from other sites. In other words, the more site A was used as a “reference” the higher it would rank. Anchored text
    links used to link to site A are also very important as well as the popularity and the relevance of the site that is
    referencing site A.
Search engine optimization                                                                                                     5

    White hat versus black hat
    SEO techniques are classified by some into two broad categories: techniques that search engines recommend as part
    of good design, and those techniques that search engines do not approve of and attempt to minimize the effect of,
    referred to as spamdexing. Some industry commentators classify these methods, and the practitioners who employ
    them, as either white hat SEO, or black hat SEO.[41] White hats tend to produce results that last a long time, whereas
    black hats anticipate that their sites will eventually be banned once the search engines discover what they are
    A SEO tactic, technique or method is considered white hat if it conforms to the search engines' guidelines and
    involves no deception. As the search engine guidelines[26] [27] [28] [43] are not written as a series of rules or
    commandments, this is an important distinction to note. White hat SEO is not just about following guidelines, but is
    about ensuring that the content a search engine indexes and subsequently ranks is the same content a user will see.
    White hat advice is generally summed up as creating content for users, not for search engines, and then making that
    content easily accessible to the spiders, rather than attempting to game the algorithm. White hat SEO is in many
    ways similar to web development that promotes accessibility,[44] although the two are not identical.
    White Hat SEO is merely effective marketing, making efforts to deliver quality content to an audience that has
    requested the quality content. Traditional marketing means have allowed this through transparency and exposure. A
    search engine's algorithm takes this into account, such as Google's PageRank.
    Black hat SEO attempts to improve rankings in ways that are disapproved of by the search engines, or involve
    deception. One black hat technique uses text that is hidden, either as text colored similar to the background, in an
    invisible div, or positioned off screen. Another method gives a different page depending on whether the page is
    being requested by a human visitor or a search engine, a technique known as cloaking.
    Search engines may penalize sites they discover using black hat methods, either by reducing their rankings or
    eliminating their listings from their databases altogether. Such penalties can be applied either automatically by the
    search engines' algorithms, or by a manual site review. One infamous example was the February 2006 Google
    removal of both BMW Germany and Ricoh Germany for use of deceptive practices.[45] Both companies, however,
    quickly apologized, fixed the offending pages, and were restored to Google's list.[46]

    As a marketing strategy
    SEO is not necessarily an appropriate strategy for every website, and other Internet marketing strategies can be much
    more effective, depending on the site operator's goals.[47] A successful Internet marketing campaign may drive
    organic traffic, achieved through optimization techniques and not paid advertising, to web pages, but it also may
    involve the use of paid advertising on search engines and other pages, building high quality web pages to engage and
    persuade, addressing technical issues that may keep search engines from crawling and indexing those sites, setting
    up analytics programs to enable site owners to measure their successes, and improving a site's conversion rate.[48]
    SEO may generate a return on investment. However, search engines are not paid for organic search traffic, their
    algorithms change, and there are no guarantees of continued referrals. (Some trading sites such as eBay can be a
    special case for this; it will announce how and when the ranking algorithm will change a few months before
    changing the algorithm). Due to this lack of guarantees and certainty, a business that relies heavily on search engine
    traffic can suffer major losses if the search engines stop sending visitors.[49] It is considered wise business practice
    for website operators to liberate themselves from dependence on search engine traffic.[50] A top-ranked SEO blog
    Seomoz.org[51] has suggested, "Search marketers, in a twist of irony, receive a very small share of their traffic from
    search engines." Instead, their main sources of traffic are links from other websites.[52]
Search engine optimization                                                                                                                        6

    International markets
    Optimization techniques are highly tuned to the dominant search engines in the target market. The search engines'
    market shares vary from market to market, as does competition. In 2003, Danny Sullivan stated that Google
    represented about 75% of all searches.[53] In markets outside the United States, Google's share is often larger, and
    Google remains the dominant search engine worldwide as of 2007.[54] As of 2006, Google had an 85-90% market
    share in Germany.[55] While there were hundreds of SEO firms in the US at that time, there were only about five in
    Germany.[55] As of June 2008, the marketshare of Google in the UK was close to 90% according to Hitwise.[56] That
    market share is achieved in a number of countries.[57]
    As of 2009, there are only a few large markets where Google is not the leading search engine. In most cases, when
    Google is not leading in a given market, it is lagging behind a local player. The most notable markets where this is
    the case are China, Japan, South Korea, Russia and the Czech Republic where respectively Baidu, Yahoo! Japan,
    Naver, Yandex and Seznam are market leaders.
    Successful search optimization for international markets may require professional translation of web pages,
    registration of a domain name with a top level domain in the target market, and web hosting that provides a local IP
    address. Otherwise, the fundamental elements of search optimization are essentially the same, regardless of

    Legal precedents
    On October 17, 2002, SearchKing filed suit in the United States District Court, Western District of Oklahoma,
    against the search engine Google. SearchKing's claim was that Google's tactics to prevent spamdexing constituted a
    tortious interference with contractual relations. On May 27, 2003, the court granted Google's motion to dismiss the
    complaint because SearchKing "failed to state a claim upon which relief may be granted."[58] [59]
    In March 2006, KinderStart filed a lawsuit against Google over search engine rankings. Kinderstart's website was
    removed from Google's index prior to the lawsuit and the amount of traffic to the site dropped by 70%. On March
    16, 2007 the United States District Court for the Northern District of California (San Jose Division) dismissed
    KinderStart's complaint without leave to amend, and partially granted Google's motion for Rule 11 sanctions against
    KinderStart's attorney, requiring him to pay part of Google's legal expenses.[60] [61]

    See also
    •   List of search engines
    •   Image search optimization
    •   Search engine optimization copywriting
    •   Search engine marketing

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Search engine optimization                                                                                                                           7

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Search engine optimization                                                                                                                              8

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Search engine optimization                                                                          9

    External links
    • Google Webmaster Guidelines (http://www.google.com/support/webmasters/bin/answer.py?hl=en&
    • Yahoo! Webmaster Guidelines (http://help.yahoo.com/l/us/yahoo/search/basics/basics-18.html)
    • Bing Webmaster Guidelines (http://help.live.com/help.aspx?mkt=en-us&project=wl_webmasters&
    • Ask.com Webmaster Guidelines (http://about.ask.com/en/docs/about/webmasters.shtml)
Article Sources and Contributors                                                                                                                                                                     10

    Article Sources and Contributors
    Search engine optimization  Source: http://en.wikipedia.org/w/index.php?oldid=397457276  Contributors: 1-555-confide, 1searchking, 8harleydog, A. B., ACDJ, ALargeElk, Aajvcad, Aapo
    Laitinen, Academic Challenger, Acidburn24m, Aff123a, Ageekgal, Agentbleu, Ahmansoor, Ahoerstemeier, Aiseo, Aitias, Akamad, Akerans, Alanpog, Alansohn, Aleksandar acca,
    AlexandiaGrahamBell, Alexandrinagal, Alexius08, Alfio, Alias Flood, Allister MacLeod, Allstarecho, AlphaShroom, Alphaseo, Aman.bahl, Ambulnick, Ameliorate!, Amir Hussein Latifi,
    Ams80, Anchoress, Andres, Andrew Hampe, Andrew Kelly, Andrewlp1991, AndyKeith, Angela, Angelusc, Angr, AnimeGod, Anna Lincoln, AnonEMouse, Antandrus, Anubhavkapoor1980,
    Anyone85, Aomarks, Apm expert, Arltomem, Arteworks, Aryavartjewelry1, As847618, Asbestos, Ash, Asiftahir, Askild, Athaenara, Avinash.avala, Avtar2006, Aymerkez, Aynom, BKalesti,
    Bagdad-bob, Balddog, Barek, Bass fishing physicist, Bastardk, Batmanand, Beanstalk, Beego2008, Beetstra, Benblackwell, Benhood, Bepcyc, Bevo, Bihco, Bill Slawski, Bill.albing, Billu999,
    Billy the Impaler, Billystut, Biot, BirchComm, BizWebCoach, Bjhanifin, Blogger11, Bloodshedder, Bluerasberry, Boated idea s, Bobby9101, Bonadea, Bongwarrior, Borgx, Bovlb, Braders17,
    Bradhenry, Brandt Luke Zorn, Brian Kendig, Brianhalacy, BrightBlackHeaven, Bruce404, Bsanders246, Businessjohn, Butros, Bvlax2005, Bücherwürmlein, C777, Cackleview, Caesura,
    Calebschmidt, Calmer Waters, Caltas, Camelia13, Can't sleep, clown will eat me, Candamir, Candle21428, Candy sha, Capricorn42, Catyoung, Cdlcbe, Ceas webmaster, CecilWard, Centrx, Ceo,
    Ceoil, CesarB, ChaTo, Chaikq, CharismatcV, CharlotteWebb, Chicago god, Chintu1992, Chochopk, Chocolateboy, Chovy, Chris 73, Chrislk02, Circeus, Citicat, Cka zug, Ckatz, Clasione,
    Clbass1, Clearwriter, Cleverclick, CliffC, Closedmouth, CloudNine, Coccyx Bloccyx, Coetzeen, Collonell, Cometstyles, Cosmic Latte, Courcelles, Cpl Hicks, CrazyAboutTech, Cretog8,
    Crithit5000, CrizCraig, Cruddy, Crysb, Crystallina, Cumbrowski, Cyberservice, DShantz, Da Joe, DanielDeibler, Danieldfaux, Daniserra, Danlev, Darnals, Darth Panda, Dataneger, Dave70,
    DaveK@BTC, David Latapie, DavidTurnbull, Davidwr, Dcgwebservices, Dcoetzee, Deathphoenix, Debjitbiswas, Dekisugi, DerHexer, Deramisan, Derek Andrews, Dev564, DevastatorIIC,
    Developer2005, Devilzadvokat, Dexteritymedia, Dhaliwal, Diberri, Digitalme, Dimitar a, Dineshverma, Discospinster, Dizzyd238, Dkatten, Dlohcierekim, Domesticmonkey, Donarreiskoffer,
    Donnahunt, Dotcomseo, Dougher, Downtown dan seattle, Dr Dec, DrDooBig, DragonflySixtyseven, Drmies, Drum guy, DrunkenSmurf, Dspradau, Dudi Scraba, Duilen, Dunemaire,
    Dynamicseo, Earthlyreason, Edokter, Edvf1000r, Edward, Eeekster, Eequor, Eheuristic, El C, Elassint, Elcobbola, Eleland, Empty Buffer, Emre D., Enauspeaker, Enhanz, Enkrates, Enuffrain26,
    Epbr123, Eran of Arcadia, Estesce, Ethan01, Euphoricweb, EurekaLott, Euvinlam, Eve1213, FCYTravis, Fabahmadi, Fahadumer, Fallschirmjäger, FatalError, Favonian, Fc liam, Felyza,
    Ferdiaob, Fireman biff, Flandidlydanders, Flcelloguy, Florentdev, Fmccown, Foober, Freekyameekya, Frost110, FrostBoost, Fubar Obfusco, Funandtrvl, Furrykef, Futurix, Fuzheado, Fuzzie,
    Fvw, G18industries, GRStearns, Ga2114, Gaius Cornelius, Gallerysites, Galloping Moses, Ganesh J. Acharya, Gatsby58, Gautammarwaha, GeoFan49, Getafreeseo, Giftlite, Giggy, Gladstein,
    Glen, Globalinflatables, Globalmarketexposure, GlobeGores, Globefrog, Gmazeroff, Gobonobo, Gogo Dodo, Gpridor, GraemeL, Graham87, Graphitesmoothie, Great Mans Job, Greyblogs,
    Grim-Gym, Gtb113, Guruweb, Gwernol, HVH, Haakon, Hackaback, Hadal, Hagene, HalfShadow, Hamilton777, Hardyplants, Harrigan, Harrybias, Harryboyles, Harthacnut, Headbomb,
    Hede2000, Helg, Hephaestos, Hetar, Highbloodpressure, Hooperbloob, Howcheng, Howfar, Hsn mhd, Hu12, I5bala, II MusLiM HyBRiD II, IRP, Iain, Ian Pitchford, Icewolf34, Iglew,
    Igorberger, Imaseo, Imasleepviking, Immunize, Indiazseo, IndigoLeftRight, Infoserve, Innv, Insomniacl, Inspector 34, Intacart, Inter, InternalStatic, Internetseo, Interspireseo, Iowasmiles,
    Irene33, Iridescent, Ishamid, IslandsTropicalMan, Israelbeach, ItBangladesh, Ivostefanov, Iwebwriter, Izno, J S Pannu, J.delanoy, JVRudnick, JYi, Jacowebmaster, Jaheal200, James.nichole,
    JamesBWatson, Jamesday, Jameshacksu, Janbellows, Janet.hightower, Jasllen69, Jason ramos, Jaudette3, Jayden54, Jcc1, Jcsquardo, Jdcompguy, JeffMHoward, Jeffmcneill, Jehochman,
    Jensonick, Jeremy Visser, Jerusalem53, Jfhallberg, Jfroelich, Jhon barkan, Jimbo16454, Jimfurr, Jittree, Jkngroup, Jma, Jmabel, Jnbwebpromotion, Joer80, Joeychgo, John Fader, Jonathan Hall,
    Jonhenshaw, JordeeBec, Josh Parris, Jpgordon, Jrtayloriv, Jukcoder, Julyo, JurgenG, Jushi, KD5TVI, Kaediem, Kamalchandran, Kamtech2010, Kardana, Katnels, KatyForward, Kazrak,
    Kcheung123, Kelley pec, Kellycasey, Kensav, Kentor1, Keyword Tool, Khalaan, Kim Bruning, Kimchi.sg, Kipironside, Kiranoush, Kjhstuph, KleenupKrew, Kmastrola, Kmkerol, KnightRider,
    Knighty123, Knox387, KooDating, Korg, Kozuch, KrakatoaKatie, Krator, Kristymartin.bizonly, Krith23, Krnntp, Kuru, KyraVixen, LDVO30, Labnics, Lamatrice, Lambodhari, Latinpafa,
    Laxminarayan108, LazyFox, Lazyjai, LeaveSleaves, Lev, Lightbulbs, Lightmouse, LinguistAtLarge, LinkKingCJ, Linkspamremover, Lior1075, LisaAndrew, LittleDan, Lkutaj, Lordmac,
    Lordthees, Luk, Lumingz, Luna Santin, Luwilt, M.alqasim, M150565, MER-C, MK8, MKoltnow, Mackan, Madein272766, Mahahahaneapneap, Majorly, Malcolm Farmer, Mamacitamamacita,
    Managedspaces, MansonP, Maple626, Margareta, Markus Kuhn, Markworthen, Masoodsabir, Masteruser23, Mathsci, Mattisse, Mattonline, Max1900, MaxPowers, Mayankgates, Mbp, Md8834,
    Mdomengeaux, Mediaguy916, Meinhaj, Mentisock, Meow, Mets501, Micburnet, Michael Devore, Michael J Swassing, Michael Martinez, MichaelCrawford, Michaelbluejay, Mike22222,
    MikeCapone, Mineshmodi63, Minghong, Misterseo, Mjhmach5, Mjlissner, Modnen, Mohamed Ouda, Mohdajmal, Monkeyman, Mononomic, MonsieurLi, Moondyne, Moreschi, Morven,
    Motanel, MrOllie, Mrseo1, Mspraveen, Mushroom, Mwanner, Mythoughts2, N5iln, NYCBrokerFREE, Nadine Peschl, NawlinWiki, NeilN, Nel03004, NellieBly, NetOracle, Netesq, Netsnipe,
    Neurolysis, Neutrality, Nexus Goof, NickelShoe, Nicola Connolly, Niduzzi, NigelR, Nik2007, Nishalegend, Nisheeth, Nitin002, Nivix, Nixeagle, Noah Salzman, Northernhenge, Not a dog,
    NotAnonymous0, Notheruser, Npowell, Nuclear696, Nvidura, Nyeguy, Obe1989, ObseloV, Octahedron80, Oda Mari, Oddity-, Oden, Officechill, Ohnoitsjamie, Oicumayberight, Oiskas, Oli
    Filth, Olly79, Omkarg, Onecanadasquarebishopsgate, Optimization1, Orphan Wiki, OverlordQ, Overmaster net, Oxymoron83, Ozuma, PC78, Pablothegreat85, Pallas44, Parhamr,
    Peakperformer1990, Pennstatephil, Pentagonsoft, Penworthy, Pepper, Perfecto, Peter Chastain, PeterMottola, Peterjones0001, Petewailes, Petrosianii, Pharaoh of the Wizards, Phgao, Philip
    Trueman, PhilipO, PhilipR, Philwiki, Piano non troppo, Pigsonthewing, PimRijkee, Pimlottc, Pjvpjv, Pmg2007, Pne, Pobrien, Poindexter Propellerhead, Polonium, PopularOutcast, Poweroid,
    Prakash Malayalam, Pravars, Priyankarules, Project mosaic, Projectphp, Pryzbilla, Purse9644, Pyrospirit, Pyrrhus16, Quadszilla, Quale38, Quinsareth, RJFJR, Raajj81, RadicalBender, RadioKirk,
    Radon210, Raelx, Ragib, Rahulv11, RainR, Rainmannn, Raj25rc, Rajkiran.singh, Rajnish357, Raju Lal, Rajupatel111, Ramu50, Rasmus Faber, RattleMan, Ravi tamada, Ravi.kumar, Rbraman,
    Rdsmith4, Rebent, RedWolf, Redbug20, Reddyreagan, Redquark, Redrocket, Reedy, Regancy42, Researchit, RexNL, Riasmaja77, Rich Farmbrough, Rich Janis, Rjwilmsi, Rmky87, Robert K S,
    Robert214, RobertG, Robinh, RockMFR, Rockethot, Rodii, Rogdov, Ronsard, Ronz, Rouier, Roux-HG, Rray, Rrjanbiah, Rthrasher, Rtmyers, Ruhrfisch, Rumschlagm, Ruzihm, Ryulong,
    S0crates9, S3000, SDSandecki, Sachinairan, Saddiqq, Saebjorn, Sagarn1, Saif1585, Saisatha, Salamurai, SallyForth123, Salvio giuliano, Sam, Sam Blacketer, Samlangdon, Samorvil, Samuel
    horse, Samwb123, SandyGeorgia, Sarlancaster, Saroger, Scarian, Schmloof, SchuminWeb, Schwnj, Scottandrewhutchins, Scottgallagher55, Sdbmaranello, Seahorseruler, Seahorsy, Search
    Engine Optimization Basic, Search Engines Web, Search-Engines-Optimization, Searchbliss, Searchdoctor, Semexpertindia, Semguru, Semnews, Sengkang, Seoadr, Seocompany, Seoguy,
    Seolinks4u, Seonaster, Seopositions, Seotactics, Seotraf, Seowiki, Seowizz, Seoz87, Sepguy, Serps, Sesu Prime, Sfacets, Sglodion12, Shabda, Shadowjams, Shahursk, Shandaman, Sharanyan,
    Sharewarepro, SheffieldSteel, Sheley, Sherwoodseo, Shierra, Shinmawa, Shinpah1, Sidonuke, Simeon24601, Simetrical, Singmarlasing, Sir mac1, Siroxo, Slavlin, Sleepyhead81, Slizer2, Slon02,
    Smallpettypeople, Smjg, Snigbrook, Snowolf, Sohan113, Soler97, Sonicelectronix, Sonny82, Sorcerak, Soumyasch, Sowmyaram1985, SpaceFlight89, Spartan-James, Species8473, SpuriousQ,
    Spyrit safe, SqueakBox, Srikanth8000, Srnec, Ssipseki2, Staceybrown281, Stakz, Starlionblue, Stateful, Steel, Stefanomanarelliwasrailroaded, Stefanomione, Stellar84, Stephen,
    Stephenchou0722, Stephenrobinsz, Stevegoble, Stevenbielik, Stevenmilne, Stickyeyes, Success4uteam, Suckmybigfatcockbitches, Suhalbansal, Superbeecat, Supercoop, Supplements, Suruena,
    Sushilover boy, Sutcliff, Swedeaction, Sweetspicelife, Sycthos, SyedHasan.Mahmood82, Synlighet, TDEmembers, TJLoop, TNLNYC, Tangotango, Tariqabjotu, Teknic, Tempshill,
    TenPoundHammer, Tentacle Monster, Terrence1019, TexasAndroid, That Guy, From That Show!, The Anome, The Rambling Man, The Red, The Thing That Should Not Be, Thehelpfulone,
    Thehollowblah, Thelb4, Thenasko, Thesecretmoneymakers, Thivierr, Thizz, Thomasdk98, ThothsBook, Thuresson, Tiddly Tom, TimBentley, Timl2k4, Timmim, TimothyDWagner, Timstaines,
    Tiptoety, Titanskc, TommyKiwi, Tomtraff, Tongxinart, ToninMaep, Tony1, Tougar, Tqbf, Treasurecoast, Tregoweth, Tresiden, Treybien, Trivialist, TronnaRob, Troxology, Trupti 610,
    Turkishbob, TutterMouse, Twinchi, Tylerdjefferson, Tzuhou, Ukmotortrade, Ukpik, Ulgaming, Ulyssesmsu, Ur1ofus, Uriah923, Usproblogger, Valfontis, Vary, Vedmaurya, Veinor, Verbal,
    Vermiculus, Versageek, Versus22, Viagra, Viajero, Vicarious, Vijay1403, Vikasamrohi, Vikkimount, Vineetrajput, ViperSnake151, Vipsem, Visor, Vistadivine.com, Vkistudios,
    Voyagerfan5761, Vssun, WATP, Wabam, Wavelength, WeShareWeOpen, Web2mayhem1, Webduckdesigns, Webmama, Wehberf, Weyes, Whateley, Whomp, WikHead, Wiki navid,
    Wikien2009, Wikiindian123, Wikipelli, Wildnetseo, William Avery, WilliamH, Willyboy104, Winchelsea, Wit, Wll6568, Wmahan, Woohookitty, Wookipedian, Work permit, Woz2, Wrockca,
    Wuhwuzdat, Xaosflux, Xerocs, Xia sha, Xobxela, Xponse, Xtzou, Xxhopingtearsxx, Y.pramod, YAM, Yardandgarden, Ybbor, Yellow7, Yerpo, Yonidebest, Youngboy2003, Zacheos, Zefrog,
    Zigger, ZimZalaBim, Zntrip, Zojj, Zzuuzz, 2117 anonymous edits

    Image Sources, Licenses and Contributors
    Image:typical-serp.png  Source: http://en.wikipedia.org/w/index.php?title=File:Typical-serp.png  License: unknown  Contributors: Jehochman, MrOllie, ZimZalaBim, 7 anonymous edits

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